It is known to embody a detection and measurement device comprising:                a first component providing an output signal whose oscillation frequency is representative of an input signal,        a reference oscillator,        a phase comparison component carrying out a comparison between the oscillations of the first component and of the reference oscillator, in particular for the purpose of a slaving by a loop of the reference oscillator to the first component, or of the first component to the reference oscillator, or of a mutual slaving, and        means of elastic coupling between the first component and the reference oscillator.        
Document U.S. Pat. No. 5,034,722 and document GB978212 describe such a device in particular.
The signal obtained as output from the phase comparison component makes it possible to have an indication of the variation of the signal from the first component, itself representative of the input signal.
The elastic coupling tends to maintain a fixed phase shift and oscillation frequencies differing slightly from the nominal frequency for the first component and the reference oscillator, once these two components are brought to nominal frequencies that are close together.
This coupling makes it possible to reduce the disturbances of the output of the phase comparison component which are due to noise intrinsic to the device, for example thermal noise or to noise extrinsic to the device, for example electromagnetic disturbances.
The action of the coupling is furthermore carried out while preserving the weak variations of the signal from the first oscillator, these weak variations being indicative of the event that one seeks to detect or to measure.
Thus the coupling makes it possible to render the output signal from the phase comparison component utilizable for the measurement of the input signal.
It is nevertheless desirable to refine the type of device presented above so as to increase the latter's measurement sensitivity, and to decrease its sensitivity to transient electromagnetic disturbances.
It is also desirable to allow operation with several sensors which may mutually influence one another and so as to allow resources to be shared between several sensors or electrodes in the case of multiplexings.